Pooled Connections Lost After 10 Minutes (600 seconds)

[Tomcat Random]

I have two instances of Tomcat 7.0.42, each on their own physical server
(RHEL6). There's nothing in front of them, I'm using IPTABLES to route 80
to 8080. They're clustered using the native Tomcat clustering. I'm using
the non blocking NIO connector.

Everything behaves as expected, except after 600 seconds (10 minutes) all
the pooled connections expire. As far as I can tell the default is to not
remove/evict pooled connections below 'minIdle' but that's what's
happening. The only thing I can find that relates to connection pools and
600 seconds is in JK, but I'm not using that. Any ideas?


Both servers have the same configuration The connection pool is configured
in context.xml:

<Resource name="jdbc/my_db"
              auth="Container"
              type="javax.sql.DataSource"
              username="tomcat_db_user"
              password="xxxxxxxxx"
              driverClassName="com.mysql.jdbc.Driver"
              url="jdbc:mysql://192.168.100.51:3306/my_db"
              maxActive="200"
              maxIdle="100"
              maxWait="20000"
              initialSize="10"
              minIdle="10"
            />

And in web.xml/

  <!-- JNDI resource for the database -->
    <resource-ref>
        <description>My Database</description>
        <res-ref-name>jdbc/my_db</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
    </resource-ref>

TIA,
Alec